A Machine to Machine (M2M) communication network includes an application node, an intermediate node and a base node. Herein the application node may be an execution node at an end, such as a smart electricity meter, a temperature sensing and control sensor, a fire alarm or a smart domestic electrical appliance and so on. The intermediate node may be an intermediate network element connecting the execution node at the end to a network side server, such as a gateway. The base node may be a network side server, and an application registered to the base node may be a management platform of an M2M service provider.
At present, in the existing art, when the base node needs to find a resource at the application node, query requests need to be transmitted to all intermediate nodes connected to the base node and the intermediate nodes forward the query requests to various application nodes. In order to facilitate an Application Entity (AE) at the intermediate node to be able to find the resource at the application node, usually a resource notification mode is adopted. That is, a notification resource corresponding to the resource at the application node is created at the intermediate node. Herein, the notification resource has a same search tag as an original resource and a link of the original resource, such that the intermediate node can conveniently find the original resource which is needed, and access the original resource according to the link. Herein the search tag is a keyword for retrieving the resource and may be considered as an identity for distinguishing different resources. In addition, for the application node, a Common Service Entity (CSE) of the intermediate node to which the AE at the application node has been registered may be called a local CSE; and other CSEs of the intermediate node and the base node to which the AE at the application node has not registered may be called remote CSEs.
However, in the existing art, the attribute of the search tag is an optional attribute. In one aspect, once the attribute does not exist, a creation notification resource request transmitted by the local CSE to the remote CSE cannot contain the attribute of “search tag”. In another aspect, for the notification resource, this attribute is mandatory. If the creation request does not contain this attribute, the remote CSE cannot create a notification resource for the original resource, consequently an insignificant notification resource will be created at the local CSE, unnecessary storage space waste will be caused and a notification resource creation failure will occur at the remote CSE.